Profile grinding machine



Oct. 12, 1943. J. w. EKSTEDT PROFILE GRINDING MACHINE Filed Oct. 15,1941 2 Sheets-Sheet l h v v E 0N 5 i.|1e 0.

M l o b. mm oo M mm t lNVENTOR John WE BY f AGENT Oct. 12, 1943. J. w.EKSTEDT I PROFILE GRINDING MACHINE 2 Sheets$heet 2 Filed 001}. 15, 1941INVENTOR .foim PIKE/vied! BY AGEN nut l6.

T'atented Oct. 12, 1943 PROFILE GRINDING MACHINE John W. Ekstedt. Union,N. J., assignor to General Tool & Manufacturing Company, a corporationof New Jersey Application October 15, 1941, Serial No. 415.019

12 Claims.

The present invention relates to a grinding machine and in particular toa new and improved means for grinding tools by the aid of a pattern.

In the manufacture of drawn articles, in particular cartridge shells;bullet jackets and the like, suitable tools such as punches and dies areused, the profiles of which must be shaped to a specified contour withinextremely small tolerances.

It is an object of this invention to provide an improved grindingmachine for speedily and accurately profiling tools, such as punches anddie shaping reamers. A further object of the invention is to providegrinding means for profiling a tool in conformity with the contour of apattern. A further object is to provide a grinding fixture comprisingunitary means supporting a fixed pattern and a rotating tool blankfreely movable over a table provided with motion limiting stops. A stillfurther object is to provide a grinding fixture having gauge means forsetting the tool blank relative to the pattern.

Other improvements, features and advantages of the invention will bemanifested in the description and drawings which exemplify one form ofthe invention, but it will be understood that variations are embodiedwithin the scope of the appended claims.

In the drawings:

Fig. 1 is a front elevation of the grinding machine.

Fig. 2 is an end elevation of the grinding machine including a sectionalview of the grinding fixture on line 2-2 of Fig. 1.

Fig. 3 is an elevation of the gauge plate on line 33 of Fig. 1, showingthe work piece and pattern in contact with the gauge.

Fig. 4 is a side elevation of a dressing tool mounted on the fixture.

Referring to Fig. 1, a grinding wheel I is mounted on the free end of ahorizontally disposed shaft ll rotatable at its opposite end in a pairof bearings I2l2 supported in a stock l3 suitably bolted or otherwisesecured to a frame [4. The wheel I0 is secured to rotate with the shaftII by a flanged collar I5 and locking H is a stepped pulley adapted tobe driven by a suitable belt connected to a power source. Although onegrinding wheel is shown, it will be understood that two or more wheelsare contemplated, one being used for roughing purposes and the other fora finished grinding; that the wheel It may be a cutter or any othersuitable shaping means; and that any other suitable or equivalent meansmay be used for rotatably supporting the wheels.

The grinding fixture comprises the work unit hereinafter described and asupporting member therefor, the latter being an L-shaped table 20 havingleg portions l8 and H3. The leg I8 is secured to the frame I4 at oneside of the grinding wheel I0, and is suitably elevated above the frameby spacer blocks IS. The leg l8 projects forwardly of the frame l4 andextends laterally so as to afford a table surface opposite the peripheryof the grinding wheel. Beneath the table portion It is secured a pair ofparallel gib members 2l-2| extending from front to rear of the table 20and substantially in line with the plane of the face of the grindingwheel. The gib members constitute guides for supporting a slidablemember or bar 22 having a substantially vertical, planar; hardened steelsurface 23 integrally formed or otherwise secured at its end adjacentthe periphery of the grinding wheel. The planar surface 23 has twofunctions, namely to act as an adjustable stop means adapted to beengaged by the end of a pattern during the guiding of the work piece ashereinafter described and to constitute an adjustable stop for guiding adressing tool 29 in the manner indicated in Fig. 4. The opposite end ofthe slidable bar 22 is suitably secured to the end of an adjusting screw25 threadedly engaged adjacent its opposite end in a hole in a plate 26which is fastened by bolts 21 to the front edge of the table 20. It willbe clear that by turning the knurled head of the adjusting screw 25, thebar 22 may be made to slide backwardly or forwardly in the guides 2|2lwhereby the planar surface 23 may be adjusted relative to a verticalplane tangen tial to the periphery of the grinding wheel. The slidablebar 22 may be readily locked in the guides by a suitable locking screw28.

The member for supporting the tool blank and the master punch or patternis hereinafter termed the work unit" and comprises a block 30 having apair of laterally extending flange portions 3|3l at the base thereof andsurmounted by a pair of axially aligned spaced collars 32-32 havingbearings 33,34 adapted to support a horizontally disposed tubularspindle 35. The bearing 34 is extended rearwardly, as shown in Fig. 2,and provided with a threaded end 34' to which a coupling 36 is secured.The coupling 33 is adapted, in a well-known manner, for coupling theusual type of flexible drive shaft 31 to the slotted end 35' of thetubular spindle 35. 38 represents the tool blank, hereinafter termed thework piece, concentrically mounted in the spindle 35 and locked theretoby a slightly tapered centralizing bushing or collet 33 which is slippedon the rear end of. the work piece and wedged between the latter and thetapered inner walls of the spindle 35. It will be understood that bythis construction a substantial portion of the shank of the work pieceis clear of the walls of the tubular spindle 35. This structural featureis particnlarLv advantageous when adjusting the work piece bothlongitudinally and concentrically relative to the spindle.

The means for supporting the forward end of the work piece comprises acircular plate 40, hereinafter termed a steady-rest. secured to the faceof one of the collars 32 by suitable means, such as screws 40' andprovided with a radial slot 4| adapted to accommodate a bronze jaw 42secured therein by a screw 43. The inner end of the jaw 32 is arcuateand is adapted to be adjusted radially to contact the shank portion ofthe work piece in order to overcome any eccentricity or vibration set upin the latter due to rotation thereof.

The tubular spindle 35 is restrained against endwise displacement in thebushings 33 and 33 by suitable means engaging the inner faces of collars32. Such means may be a hardened steel pulley M keyed by a screw 45 tothe spindle at substantially the mid-portion thereof and rotatablebetween a pair of bronze thrust washers 46-45 suitably secured on theinner faces of the spaced collars 32-32. Although bronze washers arespecified it will be understood that any other suitable material may beused. The tubular spindle may thus be driven either by the fiexibleshaft 31 or by a belt running over the steel pulley 3. Suitable oilholes 4'|4| are provided for supplying oil to the spindle.

The master punch 49, hereinafter termed the pattern, is adjustablymounted in a longitudinal hole 50 drilled through the block 30immediately below the work piece 33 and in substantially the verticalplane thereof. The drilled hole 50 is made sufficiently large so thatthe pattern may move freely therein, and means are provided foraccurately positioning and holding the pattern. Such means may comprisehardened steel end plates |5| adjacent opposite ends of the hole 50 andsecured to the respective ends of the block 30 by screw bolts 52 passingthrough longitudinal slots 52' in the plates. Each plate 5| is providedwith a centrally drilled and ground hole 53 in which one end of thepattern is supported, the size of the drilled holes 53 being such thatthe shank portion of the pattern makes a tight fit therein. Suitablelocking means such as the set screw 5| may be provided for locking thepattern against longitudinal displacement in the end plates. Each endplate 5| is adapted to be adjusted laterally by adjusting screws 5354suitably supported in studs 54'5| fixed on the adjacent flanged portions3| of the block 30 and adapted to bear against opposite ends of theplate 5|. By this construction the pattern 49 may be set in perfectvertical alignment with the work piece.

The work unit or block 30 is adapted to move freely over the surface ofthe table 20 and to this end the bottom of the block is provided withhardened steel bearing surfaces 55. Although substantially flat surfacesare shown it will be understood that spherical surfaces or rollerbearings may be used.

It will be clear that since the work piece is continuously rotated it isonly necessary for the operator to pivot the work unit through an arc ofsubstantially in order to completely profile the end of the work pieceand hence suitable stops are supported on the table for limiting thepivotal movement of the work unit, about the point of contact of thepattern with the stop plate 23, to one quadrant of a circle orsubstantially 90. In its initial position the work unit or block 30 ismounted on the table 23 with the left hand fiange 3| of the blockabutting a pair of limit stops 56 suitably fixed to the edge of thetable, the stops being adjusted to limit the displacement of the workunit to the left, as seen in Fig. 1, so that the work piece and patternlie substantially in the vertical plane of the grinding wheel. The workunit is limited in its angular displacement from its initial position toa final position by fixed stop means shown in Fig. 2 comprising alaterally adjustable pin 51 supported above the leg portion [3 of thetable 20 by a lever 58 pivotally supported on a standard 59 bolted tothe adjacent rear edge of the table.

Referring to Fig. 3, a suitable device is shown for making the initialadjustment of the work piece and pattern. It will be understood by thoseskilled in the art that an initial allowance for grinding must be madewhen adjusting the work piece relative to the pattern, and to this endsuitable gauge plates or surfaces 5D5| are integrally formed on thestandard 55, the surface 60 being set back from the plane of the surface6| by an amount substantially equal to the allowance necessary forgrinding.

In setting up the work unit the work piece is first inserted in thetubular spindle 35. The pattern is then inserted in the holes of thespaced plates 5| and adjusted laterally by the adjusting screws 54 untilthe work piece and pattern lie in exactly the same vertical plane.Thereafter the work unit is moved over the standard 58 so that the workpiece and pattern are substantially perpendicular to the plane of thesurfaces 60 and 6| respectively, the end of the pattern being broughtinto contact with the surface 5|. While the unit is in this position thework piece is moved longitudinally until its end contacts the surface60, whereupon the work piece is locked to the rotatable spindle by thecollet 39 as described above.

In operating the machine the operator moves the work unit over thesurface of the table toward the grinding wheel with the left hand flange3| of the block abutting the stops 56. As the grinding of the work pieceprogresses the end of the pattern comes in contact with the adjustablestop surface 23 which has been previously adjusted and locked in asubstantially vertical plane tangential to the periphery of the grindingwheel. From this initial position the operator pivots the work unit in acounterclockwise direction, or toward the right as viewed in Fig. 1,while holding the pattern in continuous contact with the stop surface23, until the work unit finally abuts the stop 51. When the work unitreaches this final position the pattern and work piece have beenangularly displaced through substantially one quadrant or 90 and thework piece completely profiled with a contour corresponding to that ofthe pattern.

What is claimed is:

1. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin the stock and a table supported on said frame; of a work unit freelymovable over the surface of said table, said work unit comprising workpiece rotating means and a nonrotatable pattern; adjustable stop meanscomprising a bar slidably supported beneath said table on a pair ofspaced parallel gibs; a vertical planar surface formed on the forwardend of said bar projecting above the plane of said table; an adjustingscrew supported on said table and threadedly secured in the opposite endof said bar for moving said planar surface and thereby limiting themovement of said work unit relative to the periphery of said grindingwheel; means for locking said bar; and motion limiting stop meanscomprising a pair of adjusting screws fixedly supported on one side ofsaid table and an adjustable pin pivotally supported on an adjacent sideof said table at substantially right angles to said adjusting screwswhereby the angular displacement of the work unit when pivoted about apoint on said adjustable stop means is limited to substantially 90.

2. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unitcomprising a block freely slidable on said table, spindle means forrotatably supporting a work piece in said block, adjustable platessecured at opposite ends of said block for supporting a pattern, andmeans supported on opposite ends of said block for adjusting saidplates; and motion limiting stop means secured to said table forlimiting the angular movement of said pattern and work piece relative toa point on the periphery of said grinding wheel.

3. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unitadapted to slide freely on said table, said work unit comprising a blockhaving bearing surfaces, meansfor adjustably supporting a pattern insaid block, spindle means for rotatably supporting a work piece in saidblock, said spindle meanshaving a steady rest secured to said blockadapted to support the shank of said work piece, and means for rotatingthe work piece; and stop means on said table for limiting both thelongitudinal and angular movement of said pattern and work piece whenmoved relative to a point on the periphery of said grinding wheel. g

4. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unitadapted to slid freely on said table, said work unit comprising a blockhaving bearing surfaces, bearing mean including a spindle for rotatablysupporting a work piece in said block, a steady-rest for said work piececomprising a plate secured to said block having a radially disposed slotadapted to support the shank of said work piec and a shank engaging jawsecured within said slot, means secured to said bearing spindle forrotating said spindle including a bushing for locking the rotatablespindle to said work piece, adjustable plates mounted on opposite endsof said block for supporting a pattern and adjusting-screws on oppositeends of said block for moving said plates and thereby adjusting saidpattern relative to said work piece; stop means on said table comprisinga planar vertical surface for positioning the end of the patterntangential to the periphery of the grinding wheel; and motion limitingstop means supported on said table for limiting the angular movement ofsaid work unit a said pattern is pivoted in point contact with saidplanar vertical surface.

5. In a grinding machine of the character described, the combinationwith a frame, a grinding wheel, and a table supported on said frame; ofa work unit freely movable over said table comprising a pattern and workpiece rotating means; means on said unit for adjusting sai pattern intothe vertical plane of said work piece and a' gauge secured to said tablefor adjusting the work piece longitudinally relative to said pattern.

6. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unit freelymovable over said table comprising a pattern and work piece rotatingmeans; means on said unit for adjusting said pattern into the verticalplane of said work piece; and a gauge comprising a standard secured tosaid table having a pair of gauge surfaces adapted to be contacted bysaid pattern and work piece respectively for adjusting the latterlongitudinally relative to said pattern.

7. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unitcomprising a collet for said work piece, means for rotating said collet,

and a pattern, said unit being freely movable over said table; stopmeans secured to said table for limiting the movement of said work pieceand pattern to a point tangential to the periphery of said grindingwheel; and means for supporting said stop means comprising gauge meansadapted to be contacted by said pattern and work piece for adjusting thelatter longitudinally relative to said pattern.

8. In a grinding machine of the character described, the combinationwith a frame having a bearing stock, a grinding wheel rotatably mountedin said stock and a table supported on said frame; of a work unitcomprising a rotatable collet for supporting a work piece and a fixedpattern, said unit being freely movable over said table; adjustable stopmeans comprising a vertical planar surface slidably supported on saidtable for stopping the movement of said pattern and work piece towardsaid grinding wheel at a point tangential to the periphery of saidgrinding wheel; fixed stop means secured to two adjacent edges of thetable for limiting the angular displacement of the pattern and workpiece when the pattern is pivotally moved in constant contact with saidplanar surface; and gauge means comprising a gauge plate supported onsaid table adapted to be contacted by said pattern and work piece foradjusting the latter longitudinally relative to said pattern.

9. A fixture for profiling a tool comprising, in combination, a support;an adjustable stop means comprising a vertical planar surface; a workunit movable over said support comprising, means for supporting saidwork piece, rotating means for said work supporting means, a pattern,and means for adjusting said pattern laterally relative to said workpiece; and motion limiting stops mounted on adjacent edges of said tablefor limiting the pivotal movement of the end of said pattern about apoint on said planar surface.

10. A fixture for profiling a tool comprising, in combination, asupport; a work unit comprising a sleeve for supporting the work piece,means for rotating said sleeve, and a pattern, said unit being freelymovable over said support; stop means for limiting the movement of saidwork unit; and means for supporting said stop means comprising a gaugefor adjusting the work piece relative to the'pattern.

11. A fixture for supporting a work piece in contact with the peripheryof a grinding wheel comprising, in combination, a table; a work unitfreely movable over said table comprising a rotatable sleeve forsupporting a work piece, means for rotating said sleeve, and a fixedpattern; stop means comprising a vertical planar surface slidablymounted on said table; means for longitudinally adjusting the planarsurface tangential to the periphery of a grinding wheel: motion limitingstop means for limiting the pivotal movement of the pattern when inpoint contact with the planar surface; and means for supporting saidstop means comprising a gauge fixed to said table for adjusting the workpiece relative to the pattern.

12. A fixture for profiling a tool comprising, in

combination, a table; a work unit movable over said table, said unitcomprising a block adapted to slide freely on said table said blockhaving bearing surfaces, means including a spindle for rotatablysupporting a work piece in said block a steady-rest for said work piececomprising a plate secured to one of said bearing surfaces having aradially disposed slot adapted to support the shank of said work piece,a shank engaging Jaw secured within said slot, means secured to saidbearin spindle for rotating said spindle including a collet for lockingthe rotatable spindle to said work piece; adjustable plates mounted onopposite ends of said block for supporting a pattern and adjustingscrews opposite the ends of said plates for moving said plates andthereby adjusting said pattern laterally relative to said work piece;stop means on said table comprising a longitudinally adjustable planarsurface for stopping the longitudinal movement of said pattern in aplane tangential to th periphery of a grinding wheel; and adjustingscrews fixed to said table for limiting the angular movement of saidpattern and work piece when the end of said pattern is pivoted about apoint on said adjustable planar surface.

7 JOHN W. EKSTEDI'.

